Counties of Santa Barbara, Ventura and San Luis Obispo


Steelhead Restoration - Distribution & Listing Status

Distribution and Listing Status
The historical range of steelhead occurred throughout the North Pacific Ocean from the Kamchatka Peninsula in Asia to the northern Baja Peninsula (NMFS 1996). Steelhead likely inhabited most coastal and inland streams in Washington, Oregon and California as well as many inland streams in Idaho. The current range of steelhead extends from the Kamchatka Peninsula south to at least Malibu Creek in southern California, although significant population declines have occurred in recent decades (Nehlsen et al 1991). Several factors are thought to have caused these declines. For instance, degradation and loss of over 90 percent of wetland and riparian habitats have been major sources of decline of steelhead in California. Additionally, habitat losses have occurred as a result of water diversions for agriculture, flood control and hydroelectric power, sedimentation from adjacent land use activities, and urbanization (NMFS 1996). Furthermore, recreational fishing and introduction of non-native predator species have also contributed to the decline.

Steelhead Trout in the South-Central California Coast ESU
On August 18, 1997, steelhead were listed as "threatened" by the National Marine Fisheries Service (NMFS) under the Endangered Species Act (ESA) in the Evolutionarily Significant Unit (ESU) from the Pajaro River (inclusive) to, but not including the Santa Maria River (NMFS 1997).

Historic population estimates for steelhead in this ESU vary widely. McEwan and Jackson (1996) estimated runs of 1,000 to 2,000 returning adult steelhead annually in the Pajaro River and 3,200 in the Carmel River during the mid 1960s. For the same time period, CDFG estimated runs of 27,750 individuals in some rivers of this ESU (NMFS 1996). NMFS (1996) indicated that by 1990, steelhead runs were as low as 500 fish in five rivers combined in this ESU (Pajaro River, Salinas River, Carmel River, Little Sur River, and Big Sur River).

Steelhead Trout in the Southern California ESU
On August 18, 1997, steelhead were listed as "endangered" by NMFS under the ESA in the ESU from the Santa Maria River to Malibu Creek (NMFS 1997). On May 1, 2002, NMFS extended the range of listed Southern California steelhead to the U.S.-Mexico Border.

The steelhead trout was once abundant and widespread in the coastal rivers and streams of southern California. Now, it is restricted to small populations mainly in the Santa Clara River, Ventura River, Santa Ynez River and Malibu Creek.

Historically, the Ventura River reportedly supported a substantial run of steelhead (an endangered fish) until the late 1940's when a prolonged drought and the construction of Matilija Dam apparently contributed to the decline of the species. Currently, steelhead can occur in the Ventura River below Robles Diversion Dam and portions of San Antonio Creek and its tributaries.

Links
National Marine Fisheries Service (NOAA)
Designation of Critical Habitat for Seven Evolutionarily Significant Units of Pacific Salmon and Steelhead in California
South Central California Coast Steelhead ESU Range
Southern California Steelhead ESU Range
Current Stream Habitat Distributions
Historic Stream Habitat Distributions
Southern California Steelhead Range Extension Notice - 5/1/02